Bacterial vaginosis after menopause: factors associated and women’s experiences: a cross-sectional study of Australian postmenopausal women

Introduction

Bacterial vaginosis (BV), the most common cause of abnormal vaginal discharge in women of reproductive age, is associated with significant morbidity including pregnancy complications (e.g. spontaneous abortion and premature labour), pelvic inflammatory disease, and a greater risk of acquiring a sexually transmissible infection (STI) including HIV.^1–4 It has been estimated that between 23% and 29% of women will have BV at any point in time,⁵ with prevalence higher in women who have sex with women,^6–9 women of African ethnicity,^10–15 and women who engage in intravaginal practices.^1,16 Although the aetiology is unclear, BV is characterised by a change in the composition of the vaginal microbiota. The predominant Lactobacillus species is replaced by a more diverse group of organisms including Gardnerella vaginalis, Fannyhessea vaginae (previously Atopobium vaginae), and genital mycoplasmas.^17–22 Symptoms are common and can include a thin vaginal discharge and a fishy odour.¹ Recurrence following first-line antimicrobial therapy is common and can be very distressing and have a significant impact on a woman’s self-esteem and intimate relations, affecting their quality of life.^23,24

While BV is well recognised and readily diagnosed in women of reproductive age, little is known about it in postmenopausal women, perhaps because of the considerable obstetric and gynaecological complications associated with BV in younger women. Further, while much is known about the negative impact of BV on reproductive age women’s quality of life, there is little information about its impact in postmenopausal women. A recent systematic review found that few studies have reported on BV in postmenopausal women, with prevalence estimates ranging from 2% in women undergoing elective surgery to 57% in women presenting to a gynaecology clinic with vaginal symptoms.²⁵

Given the paucity of data about BV in postmenopausal women, we conducted an online survey of Australian postmenopausal women that aimed to understand more about their experiences of BV and the factors associated with the condition after menopause.

Materials and methods

This was a cross-sectional study of Australian postmenopausal women conducted between 8 July and 8 September 2021. Participants were asked to complete an anonymous online survey.

Results

Discussion

To our knowledge, this is the first study to investigate knowledge and experiences of BV in postmenopausal women in Australia, finding that over a third had heard of BV and about 6% reported having a BV diagnosis after menopause. While a BV diagnosis before menopause was the strongest predictor of BV after menopause, it was also associated with having ever been diagnosed with an STI suggesting an association with sexual activity. Women diagnosed with BV after menopause reported being distressed with about half reporting that it had affected a sexual relationship.

We found that knowledge of BV among postmenopausal women was poor with only about one-third reporting that they had heard of BV. However, BV knowledge was associated with age, with younger women being much more likely to have heard of BV. This is not surprising given that the term ‘bacterial vaginosis’ only began to appear in the literature in the 1980s. The condition had previously been known as Haemophilus vaginalis vaginitis or non-specific vaginitis.^26,27 Most published BV research is conducted in women of reproductive age with few BV prevalence estimates available for postmenopausal women, and while our study is not a prevalence survey, it does suggest that a considerable number of women continue to experience BV after menopause.

We found that a BV diagnosis after menopause was also associated with douching. The evidence of associations between douching and BV can be conflicting^28–30 and the cross-sectional nature of our study design makes it difficult to determine causal associations and whether the douching or the BV came first. Our findings show that a BV diagnosis after menopause was associated with sexual activity. This is consistent with the substantial amount of evidence that suggests that BV is sexually transmissible^1,4,31 and that women diagnosed with BV are more likely to have a comorbid diagnosis of an STI.^3,32 Women in our study who were currently in a sexual relationship of 5 years or less in duration were more likely to report a BV diagnosis after menopause. This is consistent with evidence that suggests that people dating again later in life often lack knowledge of STIs and safer sexual practices, increasing their risk of acquiring BV and other STIs including HIV.³³ A recent study found that STIs are increasing at a faster rate in older women than in younger women.³⁴

Our survey found that, similar to reproductive age women,²³ BV in postmenopausal women can negatively impact a woman’s quality of life, requiring support and management. Further, the strongest predictor of having a BV diagnosis after menopause was having had it before menopause, highlighting the importance of primary care physicians being informed about BV and understanding that it can affect a considerable proportion of older women at some stage, so that they can discuss it with their patients. However, research shows that primary care physicians are less likely to have conversations about sexual health with their female patients after menopause and older women are less likely to raise sexual health issues with their doctors,^35,36 potentially placing them at risk of ongoing BV and its associated symptoms and complications.

The diagnosis of BV is commonly made by one of two gold standard diagnostic methods: (1) Nugent scoring; or (2) Amsel criteria. However, these methods have been developed in women of reproductive age and rely on the impact of premenopausal levels of oestrogen on key diagnostic criteria.^37,38 Both of these methods become less suitable for diagnosing BV in women after menopause as endogenous oestrogen declines,^39,40 and can hinder our ability to understand the prevalence and pathogenesis of BV in postmenopausal women. The development of a more appropriate diagnostic method suitable for BV in women after menopause is crucial.

A key strength of our study is that it is, to the best of our knowledge, one of the first studies to investigate the impact of BV on postmenopausal women’s health and wellbeing and provides data for women across a wide age range (51–90 years). However, our study has a number of limitations to be considered. This was a cross-sectional convenience sample, with women aged 51–59 years and tertiary educated women over-represented. Recall bias cannot be excluded as women were asked about BV diagnoses that may have happened many years earlier and older women were observed to have less knowledge of BV. The latter may be recall bias but may also reflect changes in terminology as BV had previously been known as non-specific vaginitis.²⁶ Selection bias also cannot be excluded as women who have previously been diagnosed with BV may have been more likely to complete the survey. Furthermore, the questions regarding sexual practices referred to the past 12 months and diagnoses reported by some participants may have been many years earlier. Therefore, some associations will be difficult to interpret given the number of years that may have elapsed. However, over half of the women who had been diagnosed with BV after menopause reported that their most recent episode was within the past 2 years and nearly all reported that their most recent episode was within the past 5 years. However, it is also important to note that these data do not represent BV prevalence estimates. Finally, most questions gave the participants the option to skip therefore there is missing data, and, with the exception of country of birth, this is limited to less than 10%.

Conclusion

Although these are not prevalence data, our study provides evidence that BV occurs in postmenopausal women, is associated with sexual activity, and impacts negatively on their lives. About half the women in our study who reported having a BV diagnosis after menopause described recurrences, distress, and a detrimental effect on their sexual relationships. This highlights the need for research into BV that is not limited to women of reproductive age and includes the development of a diagnostic method that is suitable for use in women after menopause. This would further our understanding of BV in postmenopausal women and help to address this poorly understood but important area of public health.

Supplementary material

Supplementary material is available online.